Polynucleotides, polypeptides encoded thereby, and methods of using same for increasing abiotic stress tolerance and/or biomass and/or yield in plants expressing same

A method of increasing biomass, growth rate, seed yield, and/or abiotic stress tolerance of a plant as compared to the biomass, growth rate, seed yield, and/or abiotic stress tolerance of a control plant of the same species which is grown under the same growth conditions, wherein the abiotic stress is selected from the group consisting of osmotic stress, salinity stress and nutrient deficiency, the method comprising:

• (a) overexpressing within the plant an exogenous polynucleotide encoding a polypeptide comprising the amino acid sequence set forth by SEQ ID NO:201 wherein said polypeptide is capable of increasing biomass, growth rate, seed yield and/or abiotic stress tolerance of a plant, wherein the abiotic stress is selected from the group consisting of osmotic stress, salinity stress and nutrient deficiency, wherein said exogenous polynucleotide is comprised in a nucleic acid construct which further comprises —a promoter for directing transcription of said exogenous polynucleotide in a plant cell, said promoter is —a constitutive promoter, a tissue-specific, or an abiotic stress-inducible promoter, and;
• (b) selecting from plants resultant of step (a) a plant exhibiting an increased biomass, growth rate, seed yield, and/or abiotic stress tolerance as compared to a control plant of the same species which is grown under the same growth conditions, wherein the abiotic stress is selected from the group consisting of osmotic stress, salinity stress and nutrient deficiency,
• thereby increasing the biomass, growth rate, seed yield, and/or abiotic stress tolerance of the plant as compared to the biomass, growth rate, seed yield, and/or abiotic stress tolerance of the control plant of the same species which is grown under the same growth conditions.